This invention pertains to the art of hand tools, and more particularly to an adjustable wrench type tool.
The invention is particularly applicable to an adjustable wrench for use with fluid fittings and will be described with particular reference to so called tee and cross type fluid fittings. However, it will be appreciated by those skilled in the art that the invention has broader applications and could also be used on other types of fittings and in many different environments.
Cross and tee type fluid fittings are designed to accommodate multiple inlet and outlet branches of a fluid system. Typically these inlet and outlet branches extend in generally perpendicular relation from a central body portion of the fitting. Oftentimes, fluid conduits are sealingly secured to the fluid fitting branches through use of coupling nuts and ferrules. The branches comprise necked-down portions of the fluid fitting, and each necked-down portion is externally threaded for cooperatively receiving an internally threaded coupling nut. Advancement of the coupling nuts onto the fitting branches as is known compresses the ferrules about the associated fluid conduits to sealingly conduct the conduits to the fitting.
As is expected, attaching the fluid conduits to the individual branches of the fluid fitting necessarily requires stabilization of the fitting. The coupling nuts may then be run up on or backed off of the associated branch by means of a conventional wrench. Heretofore, a pair of open-ended wrenches have been utilized in an effort to secure fluid conduits to multi-branch fluid fittings. A first open-ended wrench is secured to external wrench flats on the body portion of the fluid fitting while the second open-ended wrench is received on the desired coupling nut. The coupling nut is then run up on or backed off the externally threaded portion of the fitting branch by means of the second wrench while a user braces the remainder of the fluid fitting from rotation through use of the first wrench.
The foregoing arrangement has been found to be less than optimal since the open-ended wrenches are subject to slipping off of the fluid fitting. Although the first wrench is mated for engagement with the wrench flat surfaces on the fitting, there is no means to clampingly engage the wrench to the fitting. Further, the multi-branch arrangements are often located in hard to reach areas which complicates a secure bracing of the fitting. The required dexterity taken in conjunction with the forces necessary to tighten or loosen the coupling nuts require careful manipulation to prevent damage to the fluid system. If the fluid conduits are subject to bending or misalignment, the sealed relationship between the fitting and conduits may be disrupted.
Yet another problem associated with prior arrangements is found in the inability to accommodate various fluid fitting arrangements. Many prior wrench designs would not readily accommodate different fitting types or styles, e.g., tees and crosses without the need for alteration or difficult manipulations.
Still another problem associated with clamping type arrangements in general is that associated with overtightening. Prior arrangements have not adequately addressed this problem and as a result, fluid fittings were subject to overtightening at the time of installation.
Accordingly, it has been considered desirable to provide an adjustable wrench for fluid fittings that would securely brace fittings of different types, and include means to prevent overtightening. The present invention is believed to meet these needs in providing a tool which overcomes all of the above referred to problems and others. The subject invention provides a simple, economical wrench structure that is readily adjustable to various fluid fitting arrangements, and limits the potential for overtightening.